Glossary of Fertility Acronyms and Terms

The medical terminology and jargon-heavy terms concerning fertility treatment can be confusing. Here’s a helpful glossary of terms to help you navigate through the jargon, but don’t be afraid to ask your nurse or doctor for a further explanation if anything is unclear:

Blast or blastocyst: An embryo that has been matured past the point of 32 cells (usually 5 to 6 days after egg retrieval in IVF/ICSI) that is ready to implant.

Day 3 transfer or day 5 transfer: The amount of time the fertilised eggs (embryos) are allowed to divide outside the body before being returned to the uterus as part of IVF or ICSI treatment, where day 1 is the day of egg retrieval. Day 5 transfers generally indicate blastocyst transfers.

Donor: A woman who donates her eggs, or a man who donates his sperm, or a couple who donates their embryos, to another woman’s fertility treatment.

E2: Oestrogen.

Egg retrieval (or collection): Part of the IVF or ICSI process when the eggs are removed from the woman’s body to be fertilised with sperm or frozen.

ET: Embryo transfer. The part of the IVF/ICSI process when the fertilised eggs (embryos) are put back into the woman’s uterus.

FET: Frozen embryo transfer. Refers to the transfer of embryos that were frozen following a previous IVF or ICSI cycle – or donor cycle – and thawed at a later time and transferred back into the uterus.

FSH: Follicle-stimulating hormone.

GIFT: Gamete intrafallopian transfer. Similar to IVF, except the egg and sperm are transferred into the Fallopian tube to fertilise naturally, instead of fertilisation occurring outside of the body.

hCG: Human chorionic gonadotrophin. The pregnancy hormone measured in a pregnancy test. Also used as part of the stimulated cycle to trigger the start of ovulation.

HSG: Hysterosalpingogram. An X-ray of the uterus and Fallopian tubes that uses a dye to reveal any blockages that prevent an embryo from reaching the uterus or stop sperm reaching the egg. HSG will also reveal fibroids , polyps, and other abnormalities in the uterus.

ICI: Intracervical insemination. Like IUI, but the sperm is placed in the cervix, rather than the uterus, via a catheter.

ICSI: Intracytoplasmic sperm injection. A variation of IVF where a single sperm is injected into the inner cellular structure of the egg. This technique is used for couples in which the male partner has severe sperm problems.

IUI: Intrauterine insemination. Placing of washed and sorted sperm, via a catheter, into a woman’s uterus at the time of ovulation.

IVF: In vitro fertilisation. Eggs and sperm are collected and put together to achieve fertilisation outside the body. Otherwise known as making ‘test-tube babies’ ‘In vitro’ means ‘in glass’ referring to the little (now plastic!) dishes that are used.

LH: Luteinising hormone.

Multiples: Refers to twin, triplet, or higher order pregnancies.

NC-IUI or NC-IVF: natural cycle IUI or IVF. Fertility treatment cycles without the use of stimulating fertility drugs.

OHSS: Ovarian hyperstimulation syndrome. A rare but serious complication of fertility drugs involved in IVF or ICSI treatment, usually following the development of too many follicles, which may cause swollen ovaries or fluid in the pelvis or around the lungs.

PESA: Percutaneous epididymal sperm aspiration. The surgical retrieval of sperm using a very fine needle directly from the collecting tube above the testicles that stores sperm (epididymis).

PCOS: Polycystic ovary syndrome. A complex hormone disorder associated with irregular periods and problems such as obesity and hirsutism (excess hair growth). The ovaries contain many small cysts just below the surface, which are follicles that have not developed properly due to hormonal imbalances. Women with PCOS may find it difficult to conceive and have an increased risk of early miscarriage.

PGD: Preimplantation genetic diagnosis. Where a cell is taken from an IVF or ICSI generated embryo and analysed for genetic diseases including haemophilia, Huntington’s disease, muscular dystrophy, sickle-cell disease and Tay-Sachs, or for chromosomal defects, such as Down’s syndrome and Turner’s syndrome.

P4: Progesterone.

Recipient: A woman who receives donor eggs or embryos.

TESA: Testicular sperm aspiration. The surgical retrieval of sperm directly from the testis with a very fine needle.

ZIFT: Zygote intrafallopian transfer. Similar to IVF and GIFT except that the egg and sperm are fertilised in the lab and returned to the Fallopian tube (rather than uterus) before any cell division of the embryo.